research articledevelopment and preliminary validation of

Aletras et al. BMC Health Services Research 2010, 10:189http://www.biomedcentral.com/1472-6963/10/189

Open AccessR E S E A R C H A R T I C L E

Research articleDevelopment and preliminary validation of a questionnaire to measure satisfaction with home care in Greece: an exploratory factor analysis of polychoric correlationsVassilis H Aletras*1,2, Arsenis Kostarelis2, Maria Tsitouridou2, Dimitris Niakas2 and Anna Nicolaou1

AbstractBackground: The primary aim of this study was to develop and psychometrically test a Greek-language instrument for measuring satisfaction with home care. The first empirical evidence about the level of satisfaction with these services in Greece is also provided.

Methods: The questionnaire resulted from literature search, on-site observation and cognitive interviews. It was applied in 2006 to a sample of 201 enrollees of five home care programs in the city of Thessaloniki and contains 31 items that measure satisfaction with individual service attributes and are expressed on a 5-point Likert scale. The latter has been usually considered in practice as an interval scale, although it is in principle ordinal. We thus treated the variable as an ordinal one, but also employed the traditional approach in order to compare the findings. Our analysis was therefore based on ordinal measures such as the polychoric correlation, Kendall's Tau b coefficient and ordinal Cronbach's alpha. Exploratory factor analysis was followed by an assessment of internal consistency reliability, test-retest reliability, construct validity and sensitivity.

Results: Analyses with ordinal and interval scale measures produced in essence very similar results and identified four multi-item scales. Three of these were found to be reliable and valid: socioeconomic change, staff skills and attitudes and service appropriateness. A fourth dimension -service planning- had lower internal consistency reliability and yet very satisfactory test-retest reliability, construct validity and floor and ceiling effects. The global satisfaction scale created was also quite reliable. Overall, participants were satisfied -yet not very satisfied- with home care services. More room for improvement seems to exist for the socio-economic and planning aspects of care and less for staff skills and attitudes and appropriateness of provided services.

Conclusions: The methods developed seem to be a promising tool for the measurement of home care satisfaction in Greece.

BackgroundThe elderly in the European Union constitute a signifi-cant segment of the society, which is expected to rise inthe future [1]. In 2005 there were 79 million individualsover the age of 65 in Western and Central Europe. Thisfigure will increase to 107 million in 2025 (+ 35%) and to133 million in 2050 (+ 68%). The largest growth in thisage group will be observed for those over 80 years (+

180%). By 2030, in contrast, all other adult age groups willbe declining in size. There is therefore a gradual shiftfrom a society dominated by young individuals to a soci-ety in which the elderly will become the majority. Theneed for the provision of social services is exacerbated bythe observed social exclusion, financial difficulties andhealth problems related to this particular age group. TheWorld Health Organization has thus placed "good aging"fifth among its targets for the 21st century.

This has led to the adoption of practices which aimed atthe promotion of the well-being of the elderly on a social

* Correspondence: [email protected] Department of Business Administration, University of Macedonia, 156 Egnatia str., P.O. Box 1591, Thessaloniki 54006, Macedonia, GreeceFull list of author information is available at the end of the article

© 2010 Aletras et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative CommonsAttribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction inany medium, provided the original work is properly cited.

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as well as on a physical level. Home care programs havebeen evolving in European countries for many decadesbased on the aforementioned and comprise the mostimportant attempt to support the vulnerable social groupof the elderly [2]. As one of the few social initiatives oflocal government in Greece ten years ago, legislation wasenacted in the majority of municipalities for the elderlyand people with disabilities. The program aimed atimproving the quality of life of the enrollees. Its effective-ness nevertheless has never been formally assessed. Thisis not surprising since research on patient satisfaction bymeans of validated questionnaires is in fact very scarce inGreece [3,4].

The program of providing home care services to theelderly and disabled begun in 1996 and quickly spread tomost municipalities in Greece [5]. Seventy five percent ofthe necessary funds have been provided by the EuropeanUnion and the rest through national financing [6]. By thebeginning of 2005 there were 1084 home care units estab-lished serving 40,060 enrollees [7]. The general purposeof the program was to confront the social exclusion andinstitutionalization as well as to improve the quality of lifeof the elderly and the disabled. Priority has been given toindividuals with an inability for self-care, who lived aloneand had limited financial resources to improve their liv-ing standards and become independent.

In order to achieve these goals, social work, nursingcare and life assistance services have been used [8]. Thesocial worker is responsible, at an initial stage, for theneeds assessment of the applicants, the scheduling ofhome visits and the determination of the range of pro-vided services. Moreover, this employee is assigned withthe task of co-operating with local parties, welfare ser-vices, voluntary organizations and the linking of thehome care program with the participants and the localcommunity. His/her role also includes provision of coun-seling and emotional support to the enrollees and theircaregivers as well as admission to various institutions(e.g. hospitals, welfare, mental health units) when neces-sary. Nursing care is prevention-oriented. Information isprovided regarding the illnesses and diseases enrolleesare facing or are likely to face in the future. Nursing alsoaddresses the enrollees' nutrition. Blood tests (includingblood glucose tests), examination of vital signs and medi-cation compliance are targeted towards the preservationof health, the self-care of enrollees and the establishmentof a safe environment. Information is provided and thefamily and other caregivers are trained, so that they canhandle problems more effectively. The aide workers'assistance includes help with personal hygiene, lighthousework, grocery shopping or other small purchases,payment of bills, meal preparation and other life-assistingactivities. The interaction of all team members is oftenessential, especially for activities such as companionship,

social mobilization of enrollees, emotional and psycho-logical support and co-operation with caregivers.

In this study we developed and tested a questionnairefor measuring home care satisfaction in Greece.Although other questionnaires were available on an inter-national level, there are significant differences in the vari-ous national settings that made the development of acustomized instrument necessary. First, in several coun-tries the specific home care services enjoyed by the par-ticipants depend on private payments or a person'scontribution to a health insurance fund, whereas inGreece all services are provided free of charge by themunicipalities. They are therefore determined solely byassessing relative needs. Second, in Greece the teamwhich offers the home care services comprises mainly ofa social worker, a nurse and two aide workers, whereasother specialties (medical doctors, psychologists, physio-therapists) encountered in other countries might ormight not be included, depending on the specific munici-pality's policy. In addition, other services, such as mealpreparation, might be available to all upon requestabroad, yet only in certain programs and individuals inGreece. In general, there are important differences in thestructure and mode of provision of home care servicesbetween countries, related to the methods of financing,as well as the cultural and social factors.

The aim of this study was to measure home care satis-faction by developing an appropriate questionnaire thatcovers the Greek home care provision. The tool devisedwas psychometrically tested and subsequently the level ofsatisfaction with home care services was measured. Anovel concept in this work is the use of polychoric corre-lations in the factorial analysis and psychometric testing,which acknowledges the ordinal nature of the data, typi-cally ignored in relevant prior research.

MethodsA questionnaire in Greek was developed to measure thesatisfaction of enrollees with home care services. Itemswere phrased using a typical 5-point Likert scale with 1indicating "strongly disagree" and 5 corresponding to"strongly agree". Positively and negatively worded itemswere interchanged to avoid positive biases [9]. Negativeworded questions were therefore subsequently re-codedso that higher values would indicate higher levels ofenrollee satisfaction, and vice versa.

Items were carefully selected after an extensive litera-ture search and cognitive interviews with 15 programenrollees (of various ages, levels of education andincomes) and 15 employees (an equal number of socialworkers, nurses and aide workers) that were not includedin the main study. Items were phrased so as to avoidvagueness and biases, double negatives, double-barreledquestions and protests.


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Satisfaction items reflect all the important aspects ofthe home care program, namely effectiveness, safety,respect, attention, participation in planning, correctnessof planning, access, socialization and technical abilities ofstaff. The literature sought included theoretical papers,questionnaire validations and qualitative analyses [10-29]. Two questions included referred to general satisfac-tion from the provided home care services. Regardingsocioeconomic and demographic variables, we recordedgender, age, educational level, income, family status,enrolment duration, visit frequency and informal caregiv-ers [10]. Two more items were incorporated in order toexclude individuals that gave inconsistent responses.These had the same meaning as other questions but weredifferently phrased.

An important subsequent step in instrument develop-ment was pretesting, which took the form of cognitiveinterviews with elderly and disabled participating in theprograms [30]. There were 10 such subjects from eachgroup. These identified problems with the content andunderstanding of the questions, as well as additionalcauses of (dis)satisfaction, not captured by the instru-ment, thus enhancing reliability and content validity.Towards the same end, individuals pinpointed questionsidentified by the literature search that had to be removedfrom the instrument as being unimportant. The samepersons were approached after a revision of the question-naire and no additional issues were identified. Moreover,expert panel judgment was also exploited to ensure con-tent validity and item clarity.

We initially screened the data by assessing (Spearman's)correlation coefficients between the items capturing sat-isfaction from specific characteristics of home care andthe two items measuring overall satisfaction. Theory sug-gests that there might be a relationship apparent betweenoverall satisfaction and satisfaction from individual ser-vices [9,31]. Specifically, overall satisfaction emerges fromcustomer's evaluations of service encounters, which inturn are evaluated on the basis of service attributes (e.g.response time of the nurse). The latter are evaluated onthe basis of positive and negative events that occur duringthe encounter with the provider. In this sense, the overallevaluation of the provider might be a weighted average ofall evaluations of service attributes, the weights being theimportance assigned by the customer to each attribute.

In our context, however, one needs additional justifica-tion for excluding items from the survey, than simplyobserving insignificant correlations, for two reasons.First, we employed in this research two questions thathave been used most frequently in practice for measuringoverall satisfaction. It is nevertheless theoretically possi-ble that they do not fully cover all the aspects of satisfac-tion from the service encounter, as perceived bycustomers. Second, a single item might have to move a

great deal in order to have a significant effect on overallquality and there might be additional effects of the partic-ular item when combined with other related questions.For these reasons, statistically insignificant correlationsobserved in this study only served as triggers for furtherinvestigation of specific items.

The questionnaire was administered to enrollees ofhome care programs, who were elderly and disabled inthe age group of 65 to 90 years. An inclusion criterion tothe study entailed that the subjects should have been par-ticipating in the program for at least two months, follow-ing Westra et al. [15]. The sample was approached fromMarch 7 to April 3, 2006 with face-to-face interviews bytrained interviewers. The study was approved by theReview Board of the Hellenic Open University. Subjectswere told that their anonymity would be assured in thestudy. We excluded those who faced health disorders/problems that affected their mental state (e.g. Alzheimer'sdisease, severe stroke). Subsequently, five home care pro-grams in Thessaloniki were randomly selected from atotal of 36 programs that existed in municipalities of thecity having more than 10,000 residents: Municipality ofStavroupoli (two home care programs), Municipality ofThermaikos, Municipality of Menemeni and Pefka Vil-lage. Although a consensus is lacking, samples with atleast 200 persons and an observation-to-item ratio higherthan 5:1 are generally acceptable in this type of research[32]. The interviewers visited the houses of all 319 enroll-ees in these programs that matched the inclusion criteriaat the time of the study.

Summated scales were formed by exploratory factoranalysis [33]. The Kaiser-Meyer-Olkin measure of sam-pling adequacy and Bartlett's test of sphericity were usedto check whether the data were suitable for factor analy-sis. Values of KMO greater than 0.70 have been charac-terized as "middling" (and greater than 0.90 as"marvelous"). Bartlett's test of sphericity tests the nullhypothesis that the correlation matrix is an identitymatrix (i.e. that there is no relationship between theitems) [34].

Although in many instances they yield similar results,factor analysis was preferred to principal componentsanalysis, since the purpose of the study was to develop atheoretical construct, rather than merely perform datareduction [35]. The specific factor analyses employedunweighted least squares and varimax rotation. Theunweighted least squares method was chosen because itis robust, can be used with small samples and also whenthe correlation matrix is non-positive definite. Factorswhose eigenvalues exceeded unity were retained [36].Following other researchers, we assigned an item to a fac-tor - summated scale if its factor loading was greater than0.50 and its differences with other factor loadings of thesame item were greater than 0.20 [37,38].


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The main factor analysis carried out in this studyacknowledges the fact that the 5-point Likert scale is infact ordinal [39]. It was hence based on polychoric corre-lations. The polychoric correlation coefficient assumesthat pairs of ordinal scores are in fact generated by latentbivariate normally distributed random variables. Measur-ing the association between ordinal variables entails theestimation of the product moment correlation betweenthe corresponding normally distributed variables. Inter-estingly, a recent study that utilized a generalized poly-choric coefficient found that it does not outperform thetypical polychoric measure in cases where the sample sizeis smaller than 400 observations and the number of ordi-nal categories in the response scale is greater than three[40]. The polychoric correlation matrix was estimatedusing the two-stage procedure described in Jöreskog [41]and implemented in PRELIS v.2.8 [42]. Note that sincethe matrix was estimated in a pairwise fashion it was pos-sible to be non-positive definite. An exploratory factoranalysis was then performed entering the estimated poly-choric correlation matrix into SPSS v.15.

Since prior research has mainly assumed that the Likertscale can be treated as an interval or ratio scale, we alsoperformed, for comparative purposes, typical factor anal-yses based on Pearson correlations. In addition tounweighted least squares, we also extracted factors withprincipal axis factoring to account for the skewnessobserved in the data [43,44].

Internal consistency reliability measures the extent towhich all items within a scale are indeed capturing thesame construct. Cronbach's alpha coefficients greaterthan 0.80 indicate high levels of internal consistency,whereas values less than 0.70 suggest that the researchershould attempt deleting individual items from the scalesto examine whether consistency improves [45]. Due tothe ordinal nature of the data, an ordinal standardiseditem alpha coefficient was also derived by inserting poly-choric correlations into the simplified formula of thealpha coefficient [46,47]. Note that prior research hasexamined the potential effect of skewness to this form ofreliability coefficients and has found no impact of squareroot and log transformations on Cronbach's alpha coeffi-cients [48]. A further criterion used to assess internalconsistency reliability was inter-item correlations. Priorresearch has argued that items within a scale with lowercorrelations than 0.30 might not be sufficiently related tobe used as measures of the same phenomenon, whereasitems with correlations higher than 0.70 might be redun-dant [49]. We calculated Spearman's coefficients, thustaking into account potential skewness.

The degree to which scales are sensitive to external fac-tors in successive measurements was assessed by examin-ing test-retest reliability. The second administrationoccurred two weeks after the initial measurement. In this

study, intraclass correlations were preferred to Pearsonproduct moments coefficients because the test and retestvariables originated from the same group of individualsand the former coefficients could detect systematic errors[50,51]. There is no consensus regarding the appropriatestandards for the value of the coefficients [52]. Neverthe-less, a value of 0.70 is considered satisfactory in practice[53]. In addition, to account for possible skewness in thedata, we also employed Kendall's Tau b, which is a distri-bution-free correlation measure.

Multi-trait analysis was then performed to assess inter-nal consistency reliability, construct validity and within-scale item additivity. It is a psychometric techniqueapplied when a questionnaire is hypothesized to captureseveral distinct theoretical constructs - concepts, eachmeasured by several individual items (questions). Thecriteria assessed are [54]:

• Each item should have a high correlation with all other items in the summated scale in which it is assumed to belong (item internal consistency). 0.40 represents the lowest acceptable correlation reflecting consistency.• The correlation of an item with the sum of all other items in its scale should be higher than its respective correlations with all other summated scale scores (item discriminant validity).• For items within a summated scale, the correlation between one item and the sum of the other items should be of roughly the same magnitude for all items (equal item-own scale correlation).• Items in the same summated scale should have roughly equal variances.

If criteria 1 and 2 are not met, the groupings should bereconsidered and if criteria 3 and 4 are not met, weight-ing of items while forming summated scales should bepursued.

In the multi-trait analysis conducted we acknowledgedthe ordinal nature of the data as well as the potentialskewness of individual item scores. We therefore com-pared Pearson, Spearman, polychoric and polyserial cor-relation results, following prior research [55]. In the firstcase, we used a t-statistic for testing the significance ofthe difference between two dependent correlations [56].Spearman's Rho is suitable for ordinal data since it isbased on ranks of data. Note also that wherever a variable(multi-item scale) had more than 15 categories, it wastreated as continuous. Therefore, a polyserial correlationwas used for its association with other ordinal variables.

Construct validity was further assessed by examininginter-scale correlations. These had to be statistically sig-nificant and greater than 0.40 [57]. Furthermore, welooked at the correlations of the global satisfaction mea-sure with the other scales, as well as the correlations ofthe latter with specific participant characteristics. To


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account for data ordinality and skewness we computedpolychoric, polyserial, Spearman and Kendall's Tau bcoefficients.

Ceiling and floor effects for the created multi-itemscales were examined by assessing the percentage ofresponses falling into the highest and lowest possible sat-isfaction scores (i.e. strongly agree and strongly disagree).These are measures of the sensitivity of the tool. Finally,we computed the means and medians of the createdscales in order to measure satisfaction with variousaspects of home care as well as overall enrollee satisfac-tion. In fact, we linearly converted the scores into a 0-100point scale.

ResultsInitially, the questionnaire created included 33 itemsmeasuring satisfaction with individual aspects of homecare. For most items, Spearman correlation coefficientsbetween items and the two questions of overall satisfac-tion were statistically different from zero (p < 0.05). Incontrast, two questions meant to capture satisfactionwith individual attributes of home care had correlationswith overall measures that were insignificant. These were"I believe there should be more staff (e.g. nurses, socialworkers) involved in the program" and "The home careprogram is in need of additional specialties (e.g. physi-cians, physiotherapists)". The reason why we eventuallydecided to exclude these two items was that they seem torefer to somehow technical aspects of care that theenrollees might not be to an extent able to answer cor-rectly. Content validity does not seem to be sacrificedfrom this exclusion due to the existence of items 11 and13, which ask enrollees whether they believe they shouldbe visited more frequently and whether their needs aremet. The items measuring individual aspects of enrolleesatisfaction we used in the statistical analyses were there-fore 31. Two more questions reflected overall satisfactionwith home care programs. These are shown in Table 1(Additional file 1 contains the original questionnaire).

From the 319 home care enrollees visited, 17 wereabsent at the time of the visit and 91 refused to partici-pate in the study, yielding an initial sample of 211 face-to-face interviews. Among the participants, 93 were living inStavroupoli (44.1%), 46 in Thermaikos (21.8%), 41 inMenemeni (19.4%) and 31 in Pefka (14.7%). Six respon-dents were excluded failing the validity test by providingdifferent replies in the two control questions. Four moredid not respond to the majority of items. The final sampleconsisted of 201 usable interviews, yielding a responserate of 63% and an observation-to-item ratio of 6.48:1.There were no missing values in the remaining question-naires. This entails clarity of the constructed items. Themajority of enrollees in the final sample was women andhad little or no education. Most participants were being

visited 1-3 times each week by workers of the home careprogram and were getting additional help in their livesfrom their children. Their net monthly income was lessthan €700 (Table 2).

The KMO measure was 0.942 and Bartlett's test wasstatistically significant (p < 0.01). As can be seen in Table3, factor analysis based on polychoric correlations andperformed with unweighted least squares and varimaxrotation yielded five factors, which explain 61.16% of thevariance in the original 31 variables. One factor con-tained only one item and thus could not form a sum-mated scale by itself. Items 2, 4, 10 and 24 made up thescale "socio-economic change", questions 3, 5, 23, 28 and29 constituted the scale "staff skills and attitudes", items15 and 20 the scale "service appropriateness" and ques-tions 11 and 30 formed the scale "service planning". Notethat item 20 in the "service appropriateness" scale had infact a high factor loading also with the one-item factormentioned above. Since that factor has been disregardedfor having only one item, we decided to retain item 20and its two-item scale, despite the fact that the differencein factor loadings was less than 0.20.

The factor analysis was repeated with Pearson correla-tions. The variance explained was similarly high (62.97%)and - although there were some differences in the actualcorrelations used- the factors obtained with thisapproach were identical to those obtained with poly-choric correlations. Hence these results are not presentedhere. Furthermore, given the skewed nature of the datadocumented in Table 1, analysis was also carried out withprincipal axis factoring. Results (not shown here) indi-cated that the factors identified were identical to thosederived by unweighted least squares.

On inspection of Table 4, it is evident that Cronbach'salpha coefficients were high for the first two scales,acceptable for the "service appropriateness" scale and lowfor the multi-item scale that relates to service planning.The same conclusion was reached when we employed theordinal standardised item alpha coefficient (Table 4).Note that this latter measure also implied that the overallsatisfaction scale was more reliable than initially sug-gested. Scale data were skewed for the first three scales(skewness statistic values were -1.082, -1.921 and -1.728with a std. error of 0.172, respectively). Only the serviceplanning scale was found to be symmetrical (skewnessstatistic 0.344, st. error 0.172). We thus also examined theSpearman correlation coefficient between the items andthe scale (corrected for overlap) in which factor analysisshowed they belonged. Internal consistency was hencefurther documented for the skewed data since the nonparametric correlation statistic exceeded 0.40 in all cases(Table 5). In contrast, the scale "service planning" failedthis reliability criterion. In line with these findings, thevalues of inter-item Spearman's correlations for the first


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three scales ranged from 0.359 to 0.624. However, the twoitems we assigned to the "service planning" dimensionhad a correlation coefficient of only 0.280.

Table 6 reports test-retest correlations. 52 enrolleeswere approached and 36 had agreed to complete thequestionnaire for a second time, a response rate of69.23%. The values of the statistics are considered to besatisfactory for all scales.

Multitrait scaling yielded satisfactory results. Table 5shows that the first criterion of item internal consistency

was met for three scales, since the Pearson, Spearmanand polychoric correlations took values above 0.40. It wasnot satisfied, however, for the service planning scale. Thesecond criterion of divergent validity was fully met for allscales. Regardless of which correlation coefficient weemployed, in all cases the correlation of an item with itsown scale was higher than its correlation with other sum-mated scales. Differences were in fact significant (p <0.05). With respect to the third criterion, for the twoscales that contained more than two items, the ranges of

Table 1: Description of items measuring satisfaction with home care

Item Description Mean Median Skewness Statistic Standard Error

1 Help of staff in overcoming personal problems of the enrollee 4.16 4.00 -1.645 0.172

2 Encouragement in taking initiatives 3.75 4.00 -0.792 0.172

3 Staff disparages enrollee due to his/her personal problems 4.49 5.00 -2.285 0.172

4 Improvement in financial condition due to the provided services 3.86 4.00 -0.803 0.172

5 Staff is in a hurry to leave the house 4.10 4.00 -1.341 0.172

6 Staff informs caregivers (family, relatives) in urgent situations 3.75 4.00 -0.619 0.172

7 Staff is sensitive to issues related to the elderly or disabled 4.14 4.00 -1.410 0.172

8 Staff arrives late at its appointments 3.87 4.00 -0.985 0.172

9 Staff informs enrollee if it is going to arrive late 4.39 5.00 -1.898 0.172

10 Improvement in social functioning via companionship 3.83 4.00 -0.619 0.172

11 Inadequate frequency of visits 2.70 3.00 0.200 0.172

12 Enrollees feel more safe and secure 4.07 4.00 -1.237 0.172

13 Staff inadequately meets certain needs of the enrollee 3.68 4.00 -0.560 0.172

14 Enrollee not obliged to ask for help of others 3.99 4.00 -1.053 0.172

15 Staff forces enrollee to do things he/she dislikes 4.23 5.00 -1.417 0.172

16 Availability of staff to listen to what the enrollee has to say by phone 3.85 4.00 -0.721 0.172

17 Enrollee avoids discussing personal issues with staff due to a lack of trust 4.23 5.00 -1.539 0.172

18 Staff takes into account enrollee's views while making decisions concerning him 3.98 4.00 -1.106 0.172

19 The program's services are of little value to the enrollee 4.14 4.00 -1.469 0.172

20 Enrollee trusts staff for providing services 4.25 4.00 -1.610 0.172

21 Staff refuses to provide some services that it should 4.24 4.00 -1.713 0.172

22 Enrolment in the program was fast 4.28 5.00 -1.528 0.172

23 Staff avoids answering questions that concern the enrollee 4.18 4.00 -1.356 0.172

24 Services provided save money by not hiring a housewife or a nurse 4.11 4.00 -1.356 0.172

25 Feeling that staff will always be available if needed by enrollee 4.09 4.00 -1.181 0.172

26 Changes are made regarding the program without asking the enrollee 4.01 4.00 -0.995 0.172

27 Staff is careful while providing services (e.g. brings back receipts from shopping)

4.23 4.00 -1.290 0.172

28 Staff causes tensions with enrollee without a reason 4.44 5.00 -2.003 0.172

29 Staff knows how to serve the enrollee properly 4.04 4.00 -1.003 0.172

30 Suitability of scheduled days and hours of visits 3.26 3.00 -0.060 0.172

31 Staff listens carefully to what the enrollee has to say 4.33 4.00 -1.610 0.172

32 Expectations from the program were higher than actual services provided 3.56 4.00 -0.585 0.172

33 Enrollee would recommend the program to others 4.41 5.00 -1.731 0.172


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the various correlation coefficient values were quite nar-row. Similar values were also evident for the variances inthe four summated scales, suggesting that the last crite-rion of the multitrait analysis was also satisfied.

Inter-scale correlations are reported in Table 7. For thescales "socio-economic change", "staff skills & attitudes"and "service appropriateness" spearman, polychoric andpolyserial correlations were all higher than the suggestedliterature value of 0.40 and significant (p < 0.05), whereasKendall Tau coefficients in some cases fell a little short ofthis and yet were still statistically significant. Further-more, as expected, summated scale scores were positivelyrelated to overall satisfaction. Regarding "service plan-ning", the criterion for the inter-scale correlations wasnot met and the relationship with overall satisfaction wasweaker than that of other scales with the same globalmeasure.

Finally, Spearman's and Kendall's Tau correlations sug-gest some significant relationships of scales with respon-dents' characteristics that conform to our prior beliefs. Asexpected, net monthly income was negatively related tosatisfaction with socio-economic change, staff skills &attitudes and service appropriateness. It was unrelated to

service planning satisfaction. In addition, the duration ofenrolment might be positively related to satisfaction withservice appropriateness. These results however should beinterpreted with some caution since polychoric and poly-serial correlations lacked statistical significance (p >0.05). These latter correlations also revealed an expectedsignificant positive relation between visit frequency andsatisfaction with service planning.

The percentages of observations falling into the highestsatisfaction score category for the four summated scaleswere 7%, 15.4%, 35.3% and 3.5%, respectively. The respec-tive floor effects were very limited and equal to 0.5%,0.5%, 2% and 2.5%. Note that high ceiling effects are notuncommon in the literature [58], although some studiesdo find such effects to be more limited, that is lower than10-12% [59].

Median (mean) satisfaction from socio-economicaspects of care, staff skills and attitudes, appropriatenessof provided services and planning was 75.00 (72.17),85.00 (81.27), 87.5 (81.03) and 60.00 (59.60), respectively.Overall satisfaction was 75.00 (74.63). This means thatmost enrollees were satisfied yet not very satisfied overallwith provided services. In fact, 81.6% of all participants

Table 2: Characteristics and descriptive statistics of the final sample

Variable No. of Responses % Variable No. of Responses %

Level of Education Informal Caregivers

None 49 24.4 Relatives 25 12.4

Elementary School 117 58.2 Children 115 57.2

High School - Lyceum 26 13.0 Neighbours 29 14.4

Higher Education 2 1.0 Friends 16 8.0

University 7 3.5 Others 16 8.0

Age Monthly Net Income (€)

65-69 39 19.4 < 300 31 15.4

70-74 52 25.9 301 - 500 94 46.8

75-79 54 26.9 501-700 56 27.9

80-85 39 19.4 701-900 13 6.5

86-90 17 8.5 > 900 7 3.5

Gender Family Status

Male 75 37.3 Single 20 10.0

Female 126 62.7 Widowed 109 54.2

Visit Frequency Divorced 21 10.4

1 per month 9 4.5 Married 51 25.4

1 per fifteen days 24 11.9 Enrolment Duration

1 per week 90 44.8 ≤ 1 year 47 23.4

2-3 per week 66 32.8 (1 year - 2 years] 80 39.8

4-5 per week 11 5.5 (2 years - 3 years] 45 22.4

Other 1 0.5 > 3 years 29 14.4


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were to some extent satisfied with the home care pro-grams, whilst 9% expressed some level of dissatisfaction.A point of concern, nevertheless, relates to the lower sat-isfaction with service planning documented.

DiscussionA preliminary validation of a new psychometric tool formeasuring satisfaction with home care was conductedwith a sample of 201 individuals enrolled in five homecare programs operating in the City of Thessaloniki. Thequestionnaire had 31 items and was expressed on a Likert

scale. Although this scale has been typically considered inpractice as interval it is in principle ordinal. We havetherefore extended the usual research design to compara-tively include ordinal methods, such as polychoric corre-lations.

Results from this exploratory analysis suggested thatfour multi-item factors are associated with home care sat-isfaction: socioeconomic change (4 items), staff skills andattitudes (5 items), appropriateness of provided services(2 items), and planning of services (2 items). An addi-tional two-item scale was formed reflecting overall satis-

Table 3: Factor analysis with polychoric correlations†

Item 1st 2nd 3rd 4th 5th

1 0.485 0.326 0.324 0.190 0.190

2 0.559 0.273 0.335 0.148 0.037

3 0.454 0.658 0.180 0.078 -0.061

4 0.656 0.201 0.142 0.375 0.072

5 0.371 0.688 0.058 0.223 0.046

6 0.417 -0.079 0.553 0.128 0.227

7 0.557 0.475 0.129 0.227 0.030

8 0.278 0.307 0.186 0.048 0.361

9 0.535 0.442 0.502 0.186 0.227

10 0677 0.248 0.305 0.257 0.218

11 0.180 0.078 -0.011 0.018 0.539

12 0.597 0.327 0.446 0.265 0.132

13 0.500 0.335 0.088 0.051 0.185

14 0.550 0.265 0.199 0.426 0.207

15 0.237 0.339 0.681 0.129 -0.036

16 0.518 0.276 -0.019 0.558 0.096

17 0.366 0.328 0.251 0.511 0.092

18 0.260 0.263 0.249 0.574 0.133

19 0.435 0.116 0.244 0.455 0.321

20 0.192 0.222 0.627 0.545 0.073

21 0.212 0.508 0.247 0.461 0.040

22 0.324 0.545 0.183 0.358 0.363

23 0.286 0.633 0.109 0.250 0.284

24 0.640 0.242 0.229 0.231 0.135

25 0.509 0.370 0.393 0.427 0.177

26 0.093 0.469 0.354 0.124 0.352

27 0.237 0.416 0.435 0.362 0.216

28 0.244 0.704 0.211 0.265 0.219

29 0.162 0.636 0.394 0.226 0.126

30 -0.026 0.079 0.138 0.152 0.738

31 0.226 0.432 0.530 0.175 0.324

† Factors were extracted by applying unweighted least squares with varimax rotation (with Kaiser normalization) to polychoric correlations.


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faction with the programs. The first three multi-itemscales had satisfactory internal consistency reliability,test-retest reliability and construct validity. An additionaldimension suggested by factor analysis was "service plan-ning" which has been found to have lower internal consis-tency reliability. Future research should furtherinvestigate whether the specific summated scale can beimproved or legitimately ignored without sacrificing con-tent validity.

There are differences as well as similarities between ourscale dimensions and those found in other internationalstudies. For instance, Reeder & Chen's confirmatory fac-tor analysis lumped together three previously docu-

mented scales -namely professional/technical,interpersonal/trust and educational- into one uniquedimension [13]. Using the same instrument, Laferrierefound four dimensions of client satisfaction with homenursing care: technical quality of care, communication,personal relationships between client and provider, andservice delivery [11]. Bear et al. instead reported two fac-tors: service delivery and service sufficiency [20]. Nettenet al. and Jones et al. mentioned carer quality - opinionstowards carer, service quality and outcomes [27,60].Finally, Geron et al. classified items into the categorieshomemaker/health aide, care management service,home-delivered meal service and grocery service [22].

Table 4: Internal consistency reliability and satisfaction scores

Item Scale/Item Description Cronbach's Alpha Coefficient Mean Satisfaction Median Satisfaction

SOCIO-ECONOMIC CHANGE 0.835† (0.859)‡ 3.89 4.00

2 Encouragement in taking initiatives 0.813§ 3.75 4.00

4 Improvement in financial condition due to the provided services

0.767 3.86 4.00

10 Improvement in social functioning via companionship

0.788 3.83 4.00

24 Services provided save money by not hiring a housewife or a nurse

0.795 4.11 4.00

STAFF SKILLS & ATTITUDES 0.865 (0.894) 4.25 4.40

3 Staff disparages enrollee due to his/her personal problems

0.838 4.49 5.00

5 Staff is in a hurry to leave the house 0.834 4.10 4.00

23 Staff avoids answering questions that concern the enrollee

0.834 4.18 4.00

28 Staff causes tensions with enrollee without a reason

0.840 4.44 5.00

29 Staff knows how to serve the enrollee properly

0.835 4.04 4.00

SERVICE APPROPRIATENESS 0.756 (0.777) 4.24 4.50

15 Staff forces enrollee to do things he/she dislikes

- 4.23 5.00

20 Enrollee trusts staff for providing services

- 4.25 4.00

SERVICE PLANNING 0.520 (0.545) 2.98 3.00

11 Inadequate frequency of visits - 2.70 3.00

30 Suitability of scheduled days and hours of visits

- 3.26 3.00

OVERALL SATISFACTION 0.630 (0.728) 3.99 4.00

32 Expectations from the program were higher than actual services provided

- 3.56 4.00

33 Enrollee would recommend the program to others

- 4.41 5.00

† Summated scale's Cronbach coefficient.‡ Ordinal standardised item Cronbach alpha.§ Cronbach coefficient with specific item excluded from calculation.


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Table 5: Multi-trait analysis with Pearson, Spearman, polychoric and polyserial correlations †

Scale/Item Item - Scale Correlations

Socio-Economic Change

Mean SD Socio-Economic Change

Staff Skills & Attitudes

Service Appropriateness

Service Planning

Scaling Success§

2 3.75 0.980 0.614‡ 0.508 0.463 0.154 3

(0.522)‡ (0.423) (0.439) (0.081)

[0.609]‡ [0.494]¶ [0.506] [0.144]

4 3.86 1.096 0.718‡ 0.48 0.336 0.177 3

(0.693)‡ (0.435) (0.335) (0.139)

[0.762]‡ [0.483] [0.390] [0.194]

10 3.83 0.977 0.675‡ 0.565 0.493 0.277 3

(0.662)‡ (0.463) (0.472) (0.236)

[0.724]‡ [0.556] [0.547] [0.292]

24 4.11 1.096 0.659‡ 0.445 0.379 0.197 3

(0.573)‡ (0.487) (0.398) (0.131)

[0.683]‡ [0.476] [0.456] [0.199]

Staff Skills & Attitudes

3 4.49 0.901 0.487 0.678‡ 0.458 0.133 3

(0.416) (0.504)‡ (0.291) (0.065)

[0.544] [0.674]‡ [0.421] [0.114]

5 4.1 1.054 0.482 0.700‡ 0.404 0.202 3

(0.463) (0.609)‡ (0.321) (0.140)

[0.519] [0.688] ‡ [0.403] [0.195]

23 4.18 0.917 0.486 0.695‡ 0.415 0.325 3

(0.397) (0.615)‡ (0.287) (0.275)

[0.497] [0.709]‡ [0.386] [0.352]

28 4.44 0.893 0.496 0.671‡ 0.500 0.261 3

(0.424) (0.601)‡ (0.327) (0.147)

[0.539] [0.726]‡ [0.453] [0.257]

29 4.04 0.940 0.500 0.690‡ 0.536 0.195 3

(0.414) (0.570)‡ (0.498) (0.130)

[0.503] [0.687]‡ [0.579] [0.199]

Service Appropriateness

15 4.23 1.076 0.414 0.495 0.612‡ 0.060 3

(0.390) (0.354) (0.447)‡ (0.018)

[0.448] [0.472] [0.636]‡ [0.050]

20 4.25 0.944 0.501 0.519 0.612‡ 0.229 3

(0.434) (0.395) (0.447)‡ (0.132)

[0.522] [0.494] [0.636]‡ [0.227]

Service Planning

11 2.7 1.036 0.199 0.202 0.076 0.353‡ 3

(0.156) (0.122) (0.024) (0.280)‡

[0.219] [0.219] [0.052] [0.375]‡

30 3.26 0.930 0.204 0.256 0.185 0.353‡ 3

(0.102) (0.163) (0.112) (0.280)‡

[0.209] [0.275] [0.163] [0.375]‡

† Spearman correlation coefficients are shown in parentheses. ‡ Item-total correlation corrected for overlap. § Number of correlation comparisons in which the item-scale correlation was found to be significantly higher for hypothesized scale than for competing scale. Significance level was set at 5%. In brackets polychoric or polyserial correlations were computed, according to whether one of the two variables to be correlated had more than 15 categories and could thus be treated as continuous.


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The reasons for the observed differences between thenumber and content of scales in the home care satisfac-tion literature have not been studied. In our researchsome dissimilarity with other findings was expected dueto the differences in the Greek home care service provi-sion outlined previously.

There is some evidence to suggest that satisfaction rat-ings with home care are influenced by monthly incomeand duration of enrolment in the program. Individualswith fewer own financial resources were in most need ofhome care services and hence reported higher satisfac-tion, and vice versa. Further, the more years an enrolleehad been participating in the home care program, themore he trusted staff to carry out tasks for him and pre-sumably did not allow aides to force him do things he dis-liked. Yet one should be cautious in uncritically adoptingthese associations and explanations since some correla-tion measures lacked statistical significance.

It is important to note that the results of this study werenot influenced by the approach employed. That is,whether one assumed that the 5-point Likert scale was aninterval scale or an ordinal one had in essence no signifi-cant effect in the study findings. Similar findings fromordinal and Pearsonian exploratory factor analyses havealso been documented for the Big Five Questionnaire[39].

Finally, overall enrollees were satisfied with the homecare programs. Higher levels of satisfaction were associ-ated with the skills and attitudes of the staff and the suit-ability of services. Whereas lower levels were associatedwith the social and economic aspects of provided helpand service planning. There are no existing studies in theGreek setting with which to compare the current find-ings. Although home care services in other countries dif-fer, have been evaluated with other tools and refer todifferent populations, we simply note that findings suchas ours are not uncommon. For instance, the mean satis-

faction in this study was 74.63, whereas in a US study amean of 74.1 was reported [22].

This study has certain limitations related both to themeasurement of satisfaction and the validation of thequestionnaire. Since the provision of home care programsin Greece is decentralized and information on the charac-teristics of the population of enrollees is not gathered bythe central government, we were unable to investigatewhether our sample was representative. The sample wasin fact geographically restricted to the city of Thessalon-iki. Moreover, there were no other studies in the Greeksetting with which we could compare our findings. Thesummated scales "service planning" and "overall satisfac-tion" had low reliability values and "service appropriate-ness" a marginally acceptable Cronbach's alphacoefficient. The fact that these were all two-item scalesmight partly account for that. Nevertheless, we note thatscales comprising of only two questions have often beenfound highly reliable in the Greek setting [4]. Finally, themeasurement of satisfaction has been criticized for itsweak conceptual foundation and potential biases due toacquiescent response set [61,62].

ConclusionsSumming up, exploratory ordinal and traditional factoranalyses alongside reliability and validity tests revealedthree reliable and valid multi-item scales: socioeconomicchange, staff skills and attitudes and appropriateness ofservices. A fourth dimension -service planning- hadlower internal consistency reliability. Overall, enrolleeswere satisfied with the home care program. Futureresearch should further validate the questionnaire withthe use of confirmatory factor analysis and larger samplesfrom other home care programs. Moreover, the role ofservice planning in the determination of home care satis-faction should be further assessed.

Table 6: Test-retest reliability coefficients

Summated Scale Intraclass Coefficient†

95% CI of Intraclass Correlation

Polychoric Correlation

Kendall's Tau b Coefficient

Minimum Maximum

Socio-economic Change 0.958 0.919 0.978 0.942** 0.835**

Staff Skills & Attitudes 0.926 0.858 0.962 0.949** 0.830**

Service Appropriateness 0.815 0.669 0.901 0.894** 0.734**

Service Planning 0.946 0.898 0.972 0.982** 0.902**

Overall Satisfaction 0.891 0.799 0.943 0.936** 0.827**

† Model ICC (2,1) of SPSS v.15.0 has been used (i.e. single measure two-way random effects model for absolute agreement, see [50]).** p < 0.01 (2-tailed).


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Additional material

Competing interestsThe authors declare that they have no competing interests.

Authors' contributionsVHA conceived and designed the study, helped to finalize the tool, carried outdata analysis and interpretation, and drafted the manuscript. AK and MT

reviewed the literature, drafted the questionnaire and carried out the studyadministration. DN designed and supervised the study. AN contributed to allthe statistical analyses. All authors read and approved the final manuscript.

AcknowledgementsNo funding was provided for this research.

Author Details1Department of Business Administration, University of Macedonia, 156 Egnatia str., P.O. Box 1591, Thessaloniki 54006, Macedonia, Greece and 2Faculty of Social Sciences, Hellenic Open University, Patra, Greece

Additional file 1 Home Care Satisfaction Questionnaire. A question-naire in Greek that measures satisfaction with home care services.

Table 7: Correlations between scale scores and respondents' characteristics †

Scale/Characteristic Socio-Economic Change Staff Skills & Attitudes Service Appropriateness Service Planning

Overall Satisfaction Scale 0.689*** 0.653*** 0.402*** 0.336**

(0.570)*** (0.536)*** (0.337)*** (0.269)**

[0.472]*** [0.806]*** [0.434]*** [0.391]**

Socio-Economic Change - 0.542*** 0.491*** 0.158**

- (0.426)*** (0.388)*** (0.123)**

- [0.675]*** [0.480]*** [0.261]***

Staff Skills & Attitudes 0.542*** - 0.425*** 0.176**

(0.426)*** - (0.347)*** (0.139)**

[0.675]*** - [0.518]*** [0.296]***

Service Appropriateness 0.491*** 0.425*** - 0.058

(0.388)*** (0.347)*** - -0.049

[0.480]*** [0.518]*** - [0.115]**

Service Planning 0.158** 0.176** 0.058 -

(0.123)** (0.139)** -0.049 -

[0.261]*** [0.296]*** [0.115]** -

Age 0.005 -0.060 0.076 0.127

(0.004) (-0.048) (0.060) -0.103

[0.045] [-0.073] [0.054] [0.160]

Education -0.103 -0.024 -0.105 -0.130

(-0.078) (-0.019) (-0.090) (-0.110)

[-0.132] [-0.077] [-0.122] [-0.143]

Visit Frequency 0.026 0.076 -0.019 0.033

(0.019) (0.063) (-0.013) (0.026)

[0.060] [0.107] [0.006] [0.043]**

Income -0.215)*** -0.150** -0.157** -0.130

(-0.169)*** (-0.123)** (-0.126)** (-0.108)

[-0.203]* [-0.091]* [-0.127]* [-0.180]

Enrolment Duration 0.090 0.026 0.183*** 0.114

(0.068) (0.022) (0.142)** (0.087)

[0.074] [0.043] [0.177] [0.096]*

† Data outside parentheses are Spearman's correlations, whereas figures inside them represent Kendall's Tau b correlations. Polychoric or polyserial correlations are reported inside brackets.*** p < 0.01 (2-tailed).** p < 0.05 (2-tailed).* p < 0.10 (2-tailed).

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